Area Forecast Discussion
Issued by NWS Bismarck, ND

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS63 KBIS 160853

Area Forecast Discussion
National Weather Service Bismarck ND
253 AM CST Thu Nov 16 2017

.SHORT TERM...(Today and tonight)
Issued at 253 AM CST Thu Nov 16 2017

Stratus during the morning over a large portion of central ND is
the highlight in the near term. A warm frontal passage today,
followed by a cold frontal passage tonight with a slight chance of
a wintry mix are the other highlights in the short term period.

Per satellite, surface observations, and webcams, an area of
stratus continues along and east of a line from Crosby to Tioga,
to Glen Ullin, Bismarck and into Wishek. This is initialized well
by the HRRR/GFSLamp/and RAP13 Ceiling Forecast, which begins to
erode and retreat the stratus from southwest to northeast between
13z-15z, completing the journey in the Turtle Mountains by late
afternoon. Concur with this idea as this follows the location and
passage of the sfc-850mb baroclinic zone/warm front, with low
level winds veering from southeast to southerly and advecting in
drier air. Although there will be a depletion of low level clouds,
warm air advection/rising air will continue to favor a mostly
cloudy day as mid/upper level clouds stream from west to east.

The latest water vapor imagery shows an upper low/longwave trough
located over western British Columbia. A lead shortwave trough
was seen over west central ALberta. Forecast models initialize
this shortwave well, and forecast to move it into eastern Ontario
by 12z Friday. Surface low pressure associated with the mid level
shortwave was located in far southeastern British Columbia, and
will deepen as it moves east to northeast today through tonight.
In doing so, and as mentioned above, strong warm air advection
continues ahead of this system through the daylight hours, with
the aforementioned warm front moving from west to east and into
the Turtle Mountains and James River Valley by 00z Friday. A cold
front emanating from the surface low as it moves into Saskatchewan
and Manitoba tonight, will push across wester and central ND.
Enough large scale ascent per NAM/GFS for a slight chance of a
wintry mix along and behind the front. The high resolution models
are pretty much void of any precipitation, with the
GFS/ECMWF/Canadian producing a narrow line of light precipitation.
The cold front overall is weak, so the above/slight chance seems
reasonable and will follow.Highs today will range from the mid 20s
in the Turtle Mountains to the upper 40s to lower 50s in the

.LONG TERM...(Friday through Wednesday)
Issued at 253 AM CST Thu Nov 16 2017

Friday will see an Alberta clipper slide int eastern Montana
during the afternoon. A mid/upper level shortwave will also shift
east from southern Montana into western/central South Dakota.
Synoptic scale ascent atop of low level frontogenesis across and
sufficient mid level lapse rates/around 7C/km will result in a
chance for rain/snow south of Interstate 94 Friday. Much colder
again behind the clipper Saturday with highs in the 20s, to upper
30s southwest. Northwest flow aloft continues Sunday with a dry
day and highs rebounding back into the 30s and 40s.

Beyond Sunday, timing differences between the GFS/ECMWF becomes
readily apparent. Both agree that another clipper type cold front
will sweep through, with the GFS signaling it during the day
Monday, while the ECMWF does so Monday night. Either way, limited
precipitation, but strong winds advertised by both models could
result in a solid high end wind advisory and/or high wind warning for
western/central ND. The pattern remains progressive, with a
break/dry day Tuesday behind the clipper, followed by a couple of
warm air advection events. Light precipitation associated with the
warm air advection per GFS, but mostly dry on the ECMWF. With the
fast nature/progressive flow at this time through the long term
period, not expecting any widespread long duration precipiation
events. High temperatures will fluctuate quite a bit, with the
coldest air Tuesday behind the clipper - highs in the 20s for most
locations. Sunday/Monday/Wednesday/Thursday, highs will be in the
30s and 40s.


.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 253 AM CST Thu Nov 16 2017

Mvfr/ifr cigs at KMOT/KBIS/KJMS through Thursday morning.
Southeasterly winds will increase to between 15kt and 30kt from
12z-20z Thursday. Winds will lighten and begin veering to the
southwest and west as a cold front approaches northwest ND near
the end of this Taf period.




AVIATION...JJS is the U.S. government's official web portal to all federal, state and local government web resources and services.